New question #700872 on Yade: https://answers.launchpad.net/yade/+question/700872
I want to set the flexible boundary in Yade. >From the answer https://answers.launchpad.net/yade/+question/254339 I found that there are several options to achieve this. Such as the bonded particles, and the flexible membrane by woo. But I want to try another way: [1] finish the same task in Fig.9 as this paper: https://ascelibrary.org/doi/full/10.1061/(ASCE)GM.1943-5622.0001001 [2] In the below paper, the author set the boundary as the bonded particles, But I want to import velocity (stress) on each particle. [3]Maybe we can try to set the moving rigid boundary so that So we can look at it approximately as a flexible boundary? I do not know which way is the best and achievable. Any reply would be a grateful appreciate. My Yade code is as followed, which was modified from the Oedemetric Test from the Examples, and I do not know how to modify it. ################################################# # load parameters from file if run in batch # default values are used if not run from batch readParamsFromTable(rMean=.03,rRelFuzz=0,maxLoad=1.5e4,minLoad=1e1) # make rMean, rRelFuzz, maxLoad accessible directly as variables later from yade.params.table import * # create box with free top, and ceate loose packing inside the box from yade import pack, plot O.bodies.append(geom.facetBox((1,0,1),(1,.03,1),wallMask=31)) #O.bodies.append(geom.facetBox((0,0,0),(.5,.03,.5),wallMask=31)) sp=pack.SpherePack() sp.makeCloud((0,0,0),(2,0.03,2),rMean=rMean,rRelFuzz=rRelFuzz) #sp.makeCloud((0,0,0),(-0.5,0.03,-0.25),rMean=rMean,rRelFuzz=rRelFuzz) sp.toSimulation() O.engines=[ ForceResetter(), # sphere, facet, wall InsertionSortCollider([Bo1_Sphere_Aabb(),Bo1_Facet_Aabb(),Bo1_Wall_Aabb()]), InteractionLoop( # the loading plate is a wall, we need to handle sphere+sphere, sphere+facet, sphere+wall [Ig2_Sphere_Sphere_ScGeom(),Ig2_Facet_Sphere_ScGeom(),Ig2_Wall_Sphere_ScGeom()], [Ip2_FrictMat_FrictMat_FrictPhys()], [Law2_ScGeom_FrictPhys_CundallStrack()] ), NewtonIntegrator(gravity=(0,0,-9.81),damping=0.5), # the label creates an automatic variable referring to this engine # we use it below to change its attributes from the functions called PyRunner(command='checkUnbalanced()',realPeriod=1,label='checker'), ] O.dt=.5*PWaveTimeStep() # the following checkUnbalanced, unloadPlate and stopUnloading functions are all called by the 'checker' # (the last engine) one after another; this sequence defines progression of different stages of the # simulation, as each of the functions, when the condition is satisfied, updates 'checker' to call # the next function when it is run from within the simulation next time # check whether the gravity deposition has already finished # if so, add wall on the top of the packing and start the oedometric test def checkUnbalanced(): # at the very start, unbalanced force can be low as there is only few contacts, but it does not mean the packing is stable if O.iter < 5000: return # the rest will be run only if unbalanced is < .1 (stabilized packing) if unbalancedForce() > .1: return # add plate at the position on the top of the packing # the maximum finds the z-coordinate of the top of the topmost particle O.bodies.append(wall(max([b.state.pos[2] + b.shape.radius for b in O.bodies if isinstance(b.shape, Sphere)]), axis=2, sense=-1)) global plate # without this line, the plate variable would only exist inside this function plate = O.bodies[-1] # the last particles is the plate # Wall objects are "fixed" by default, i.e. not subject to forces # prescribing a velocity will therefore make it move at constant velocity (downwards) plate.state.vel = (0, 0, -.05) # start plotting the data now, it was not interesting before O.engines = O.engines + [PyRunner(command='addPlotData()', iterPeriod=50)] # next time, do not call this function anymore, but the next one (unloadPlate) instead checker.command = 'unloadPlate()' def unloadPlate(): # if the force on plate exceeds maximum load, start unloading if abs(O.forces.f(plate.id)[2]) > maxLoad: plate.state.vel *= -1 # next time, do not call this function anymore, but the next one (stopUnloading) instead checker.command = 'stopUnloading()' def stopUnloading(): if abs(O.forces.f(plate.id)[2]) < minLoad: # O.tags can be used to retrieve unique identifiers of the simulation # if running in batch, subsequent simulation would overwrite each other's output files otherwise # d (or description) is simulation description (composed of parameter values) # while the id is composed of time and process number plot.saveDataTxt(O.tags['d.id'] + '.txt') O.pause() def addPlotData(): if not isinstance(O.bodies[-1].shape, Wall): plot.addData() return Fz = O.forces.f(plate.id)[2] plot.addData(Fz=Fz, w=plate.state.pos[2] - plate.state.refPos[2], unbalanced=unbalancedForce(), i=O.iter) # besides unbalanced force evolution, also plot the displacement-force diagram plot.plots = {'i': ('unbalanced',), 'w': ('Fz',)} plot.plot() O.run() # when running with yade-batch, the script must not finish until the simulation is done fully # this command will wait for that (has no influence in the non-batch mode) waitIfBatch() -- You received this question notification because your team yade-users is an answer contact for Yade. _______________________________________________ Mailing list: https://launchpad.net/~yade-users Post to : yade-users@lists.launchpad.net Unsubscribe : https://launchpad.net/~yade-users More help : https://help.launchpad.net/ListHelp
